SARS-CoV-2 infection augments species- and age-specific predispositions in cotton rats.

Heterogeneity of COVID-19 manifestations in human population is vast, for reasons unknown. Cotton rats are a clinically relevant small animal model of human respiratory viral infections. Here, we demonstrate for the first time that SARS-CoV-2 infection in cotton rats affects multiple organs and systems, targeting species- and age-specific biological processes. Infection of S. fulviventer, which developed a neutralizing antibody response and were more susceptible to SARS-CoV-2 replication in the upper respiratory tract, was accompanied by hyperplasia of lacrimal drainage-associated lymphoid tissue (LDALT), a first known report of mucosa-associated lymphoid tissue activation at the portal of SARS-CoV-2 entry. Although less permissive to viral replication, S. hispidus showed hyperplasia of bone marrow in the facial bones and increased pulmonary thrombosis in aged males. Augmentation of these features by SARS-CoV-2 infection suggests a virus-induced breach in regulatory mechanisms which could be devastating for people of all ages with underlying conditions and in particular for elderly with a multitude of ongoing disorders.

The need for integrated research autopsies in the era of precision oral medicine.

BACKGROUND: Autopsy has benefited the practice of medicine for centuries; however, its use to advance the practice of oral health care is relatively limited. In the era of precision oral medicine, the research autopsy is poised to play an important role in understanding oral-systemic health, including infectious disease, autoimmunity, craniofacial genetics, and cancer. TYPES OF STUDIES REVIEWED: The authors reviewed relevant articles that used medical and dental research autopsies to summarize the advantages of minimally invasive autopsies of dental, oral, and craniofacial tissues and to outline practices for supporting research autopsies of the oral and craniofacial complex. RESULTS: The authors provide a historical summary of research autopsy in dentistry and provide a perspective on the value of autopsies for high-resolution multiomic studies to benefit precision oral medicine. As the promise of high-resolution multiomics is being realized, there is a need to integrate the oral and craniofacial complex into the practice of autopsy in medicine. Furthermore, the collaboration of autopsy centers with researchers will accelerate the understanding of dental, oral, and craniofacial tissues as part of the whole body. CONCLUSIONS: Autopsies must integrate oral and craniofacial tissues as part of biobanking procedures. As new technologies allow for high-resolution, multimodal phenotyping of human samples, using optimized sampling procedures will allow for unprecedented understanding of common and rare dental, oral, and craniofacial diseases in the future. PRACTICAL IMPLICATIONS: The COVID-19 pandemic highlighted the oral cavity as a site for viral infection and transmission potential; this was only discovered via clinical autopsies. The realization of the integrated autopsy's value in full body health initiatives will benefit patients across the globe.

The "oral" history of COVID-19: Primary infection, salivary transmission, and post-acute implications.

Severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2), the causative agent of COVID-19, has led to more than 3.25 million recorded deaths worldwide as of May 2021. COVID-19 is known to be clinically heterogeneous, and whether the reported oral signs and symptoms in COVID-19 are related to the direct infection of oral tissues has remained unknown. Here, we review and summarize the evidence for the primary infection of the glands, oral mucosae, and saliva by SARS-CoV-2. Not only were the entry factors for SARS-CoV-2 found in all oral tissues, but these were also sites of SARS-CoV-2 infection and replication. Furthermore, saliva from asymptomatic individuals contained free virus and SARS-CoV-2-infected oral epithelial cells, both of which were found to transmit the virus. Collectively, these studies support an active role of the oral cavity in the spread and transmission of SARS-CoV-2 infection. In addition to maintaining the appropriate use of personal protective equipment and regimens to limit microbial spread via aerosol or droplet generation, the dental community will also be involved in co-managing COVID-19 "long haulers"-now termed Post-Acute COVID-19 Syndrome. Consequently, we propose that, as SARS-CoV-2 continues to spread and as new clinical challenges related to COVID-19 are documented, oral symptoms should be included in diagnostic and prognostic classifications as well as plans for multidisciplinary care.